Thermostatic signal-operating device



Dec. 18, 1923. 1,478,084

F. G. WHITTINGTON THERMOSTATIC SIGNAL OPRATING DEVICE Filed Feb. 1l 1921 vso Patented Dec. 18, 1923.

UNITED STATES PATENT OFFICE.

FREDERIK G. WHITTINGTON, OF CHICAGO, ILLINOIS, ASSIGNOB .lO STEWART-WAR- NERVSPEEDOMETER CORPORATION, OF CHICAGO, ILLINOIS, A CORPORATION OF VIRGINIA.

THERMOSTATIC SIGNAL-OPERATING DEVICE.Y

Application led February To all whom it may concern.'

Be it known that I, FREDERIK G. WHIT- TiNeToN, a citizen of the United States, residing at the city of Chicago, in the county of Cook 'and the State'of Illinois, have invented certain new and useful Improvements in Tbermostatic Signal-Operating Devices, of which the following is a specification, referencebeing had to the accompanying drawings, forminor a part thereof.

The purpose of this invention is to provide an improved construction and mount of a thermostatic device for operating a signal, particularly designed for indicating or signaling the temperature of an automobile engine. It consists in the elements and features of construction shown and described, as'y indicated in the cl'aims.

In the drawings:

Figure 1 is a perspective view of a portion of an engine equipped with this device for showing its relation in general to the engine structure and signal.

Figure 2 is a section at the line, 2-2, on Fi re 1..

4igure 3 is a section at the line, 33, on Fi re 2.

igure 4 is a section at the line, 4.-4, on Figure 3. v

In the structure shown in the drawings, a'portion of the engine body is shown 'at A. A signaling device is shown at B,

mounted upon the top of the radiator. C is the casing enclosin the thermostatic circuit-controlling 3 devices. The circuit wires are shown at y F is a hanger by which the casing, C, is mountet and clamped in position against the hot wall of the engine.

The particul'ar construction of casing and circuit-controlling devices therein will be first described. The casing is substantially a parallelogrammatic box. double walled with interspace between the walls occupied preferably by insulating material. The lnner casing member, that is, the one which forms the inner'of the interspaced walls, comprises the two parts, 1 and 2, substantially in the form of an open-sided box with an inter-telescoped cover, 1, being the box member and 2 the cover member, the member, 1, having bosses, l, l, struck inward in proper position for stopping the cover member, 2. The binding posts and n, 1921. serial No. 444,134.

the adjusting screw for the circuit terminals and thermostatic element are all mounted on the cover member 2, 3 and 4, being the terminals from which the circuit wires run to two signals to be operated, 5 being a thermostatic or temperature-responsive element having its contact point, 5, at the free end for vibrating between'and making contact Yalternately with the terminals, 3 and 4. 6, 7 and 8 .are bindin posts, respectively, for the termin'als an the temperature-responsive member. 9 is an adjust-ing screw hereinafter' more particularly described for adjusting the terminal, 3. 'The outer casing member, 10, is substantially of box form with an open side adapted to be telescoped over the inner box member, along a dimension at right angles to the dimension along which the cover 2, of the inner box mem er is telescoped into the other part 1, of said inner member; and to facilitate thus applying the outer member to enclose the inner member, the side of said outer member 10, which corresponds to the side which constitutes the cover of the inner member from which the bindin post projects is notched to accommodate t e binding posts in applying said outer member over the inner. The interspace between the two members, 1 and 10, is preferably filled with heat-insulating material; and preferably this material is in fabric form, such as asbestos sheet or felt, adapted to maintain its form and dimensions, as- 'distinguished from a powder or granular material which might equally serve the mere urpose of insulation. The reason for prefbrring insulating material 0f the character stated rather than granular, is that the insulating material is to be relied upon for definitely spacing the members, 1 and 10, apart 'on all sides, and in reality, constituting the means for holding the inner member positioned when the outer member is definitely mounted, without any direct attachment to the inner member, whose position is therefore determined b the distribution of the material which lls the interspace between the two members, 1 and .10. Conveniently, the insulating sheet is applied in two pieces, one constituting a strip, 11, encompassing the periphery of the box member, 1, on four sides, the other a sheet, 11, dimensioned to fit into and cover the without insulation at the open side of the outer member, so that when the entire casing with the contained terminal members and temperature-responsive member is mounted against the side of the engine, said side wall, 2a, of the inner member l, will come into direct contact with the hot wall of the engine. lit will be observed that the outer casing member, 10, is applied to enclose the inner member, 1, by telescoping movement with respect to said inner mem.

ber in the direction in which the entire casing is to be pressed against the engine on which it is to be mounted, so that this pressure for mounting and holding the device in position on the engine operates also for holding the outer casing member securely in relation to the inner member as enclosing the latter.

lt is desirable that this device should be susceptible of being mounted upon the engine which it is to serve without the neces'- sity of doing any work upon the engine it'-l self by way of making bolt holes or the like for securing the device. llt is also desirable that the mounting device should not be in such relation to either of theparts of the casing as to operate as a heat conductor either to or from the inner casing member, 1. To provide for the mounting consistently with both of these desirabilities, the outer casing member, 10, has upon the wall opposite its open side an eXteriorly-protruding inwardly-hollow boss, 20, and there is provided a clamping or mounting device, F, which is in the form of an L-shaped or angle bracket or hanger having one limb, 31, provided with a bolt hole, 31a, by which it may be engaged under the head or nut of any bolt of the engine structure which is conveniently situated for that purpose, as the bolt, 40, seen in Figure l, protruding from the upper side of the engine; and the other limb of said angle bracket has an exteriorlyprotruding hollow boss, 33a., adapted to seat upon the hollow boss, 20, of the outer casing member, 10, as seen in Figure 2. rlhe limb, 32, of said angle bracket is preferably made extensible by being made in two parts, the terminal part 33, which has the boss, 33a, being applied to the other part secured by a clamping bolt, 34, taking through an eX- tended slot, 33", in said part, 33, so as to permit a range of vertical adjustment of the casing n the side of the engine against which it is to be pressed. The device is aca-racen thus accommodated to engines of varying dimensions, and having convenient fastening bolts in diderent positions relatively to the area at which it is convenient or desirable to apply the device for deriving the heat of the engine. i v

" @n account of the varying structure of different engines and the varying thickness of theirdifferent walls, and other variations edecting the relative temperature of the interior and exterior of the engine, it is necessary to calibrate the device for the particular engine to which it is applied, and this is accomplished by providing for adjustment of one or the other or both of the circuit ter- 4minals with respect tothe temperatureresponsive elements which .vibrates between them. lin the device as shown, it is intended that the terminal, 4, shall be connected with a signal, as for example a green light, which shall be at all times illuminated while the engine is cold and at any higher not unsafe temperature; and it is intended that the ter- Y minal, 3, shall be connected to a signal, as a red light, to be illuminated when the engine approaches an unsafe temperature; and it is designed that when the temperature becomes absolutely unsafe, the green light shall be extinguished and the red light only shall be displayed. To this end the terminal, 4, is made of li ht spring whose fleXure will impose upon t e temperature-responsive element, 5, only .a negligible amount of work, and that the normal position of the parts will be as shown in Figure 3, with the contact terminal, 5a, of the temperature-responsive element 5, in contact with the end of the circuit terminal, 4, the said terminal, 4, being under these circumstances,-that is, when the engine is cold,-lexed somewhat from its normal position, so that it will tend to react -toward the terminal, 5a, and follow up that terminal as the latter moves toward the terminal, 3, on rise of temperature, and will continue thus to follow up until the contact, 5, makes contact with the terminal, 3. Assuming that the highest temperature of the circulatory coolin system of the engine consistent with sa ety is say, 200 degrees Fahrenheit, this Contact of the terminal, 5a, with the terminal, 3, will occur when the temperature of the cooling water is say, about 180 degrees Fahrenheit, and by the time the temperature has arisen to the danger point of 200 degrees Fahenheit, the contact button, 5a, should be out of contact with the terminal, 4, that is, should have moved beyond the limit of reaction of the terminal, 4, to its normal position, so that, thereafter, while the temperature remains at the Ihigh point or rises, the red light only will be displayed. In order to obtain this result, the device is calibrated after it is mounted upon the engine which is to be served, by bringing the engine to the temperature at which the water in the circulatory system is heated to 200 degrees Fahrenheit, and operating the adjusting screw, 9, to cause the red lightk only to be displayed, indicating that the Contact button, 5a, has made contact with the terminal, 3, and withdrawn from contact with terminal, 4. In original construction the -position and tension of the two terminals with respect to each other and the temperature-responsive element will be such that initially the terminal, 4, will be iexed from its normal position to such an extent that its reaction to normal position will cause it to follow the contact button, 5a, of the temperature-responsive element to a temperature approximating the dangerous temperature within the number of degrees estimated to be the maximium difference between change of temperature of the cooling water and the resulting or contemporaneous change of temperature experienced by the temperatureresponsive element, so that in any event ywhen the terminal, 3, has been adjusted as above described, the contact button, 5a, will not be withdrawn from contact with the terminal, 4, until .after said opposite end of said contact button, 5a, has made contact with the terminal, 3, so that one light or the other will always be displayed, some variation being permissible as'to the overlap or change of temperature through which both lights will' be displayed. It will be understood that the reason for providing that one light or the other shall always be displayed is that the signal operated may serve not only as a temperature signal, but also as an ordinary vvehicle-position-indicating light.

It is found that a very considerable range of adjustment is necessary to be provided for with respect to the terminal, 3, to calibrate the device for different engines and it is for this .reason that it is mounted in the form shown, being retlexed upon itself for a portion between its binding-post securement and the contact end, as seen at 3b, and the initial limb of this retieXion viz. the portion extending directly from the binding post to the bend,-is apertured as seen at 3, so that the adjusting screw, 9, may extend through said aperture to impinge upon the other limb, thereby gaining the advantage of the resiliency of they bar throughout the entire extent from the binding post securement around the bend to the point of contact of the adjusting screw, 9, including the especial resiliency of the bend; and by this construction it will be seen that the adjustment of the contact end of this terminal 3, is effected by movement almost directly transverseto its length, as distinguished from movement about a pivot, which would be the character of the movementif, having the same length from the binding post to the Contact end, it were made without any bend throughout that length.

It has been found that when the casing which encloses the circuit terminals and temperature responsive element. is occupied by air the response to temperature changes is not reliablyy uniform throughout the length of said element, and the deflection upon a given change ot' temperature of the engine is not the same in all cases. To overcome this ditiioulty the casing, C, is preferably filled with a rather' heavy oil, indicated at Gr, which tends to become uniformly heated throughout and so tends to cause the temperature responsive element to have equal temperature throughout its length, and to acquire change of temperature with equal promptness under all circumstances. 40 is a removable cap Jfor closing the filling aperture through which the oil may be supplied to the chamber, C.

I claim 1. A device for the purpose indicated comprising a casing having double walls interspaced on all sides but one; electric circuit terminals and a temperature responsive element and binding posts for connecting them respectively with an electric circuit mounted on the inner of said interspaced casing walls and projecting vacross the interspace and through the outer wall; the outer-wall-casing member being in boxform, having an open side; heat-insulating material interposed in the interspace between said casing members for holding them spaced apart, and means supportino the device engaging the outer casing member only.

2. In the construction defined in claim l, foregoing, the heat-insulating material being a fabric adapted to maintain its form and dimensions, whereby the spacing between the walls at the several sides is maintained in accordance with the thickness of said fabric at said sides respectively.

3. In the construction dened in claim l, foregoing, the inner casing member com prising two parts which are telescoped together for closing the casing, the binding posts being all mounted upon the same wall of one of said parts, and the outer casing member of box form being adapted to be telescoped onto the inner member, for enclosing the latter, in the direction of a dimension at right angles to-the dimension upon which the two parts of the inner casing member are telescoped together, whereby said outer casing member locks the two parts of the inner casing member in' their telescoped relation. l

4. A. device forthe purpose indicated comprising a casing adapted to be mounted against the wall of an engine; electric-circuit terminals and a thermostatic member and binding posts by which they are mountllt) ed in the casing, the thermostatie member having a free end positioned for Avibrating between the circuit terminals under temperature changes, one of said terminals being retlexed upon itself between its vbinding post sccureinent and its ciinuitelosing Contact end, and an adjusting screw set through. the using Wall and extending past one limb of said reexure for impinging on the other limb to silex said terminal at the bend for adjusting the contact end relatively to the thermostatio member.

5K. A thermostatic electric circuit closing device comprising a casing9 adapted to be held pivessed against a hot part of an engine? said casing liaving a double Wall at all sides except that which is pressed against the engine, means for .insulating tlie enclosed part from exterior mperature except that et the engine, the outer Wall having means for engaging a pressure arma and suoli pressure arm adapted tor such engagement and having a bolt hole tor securing it under tlie head or nut ot any convenient bolt ot the en` gin-e stinuctuna1 6. ln the construction defined in claim 5, toregoing7 the pressure-arm-engaging means et the easing being an interiorly hollow and eXteriorly-protrudlng loess', whereby the thermal insulation from tlie pnessune arm is f incteased.

7., t device for tlie purpose indicated, con sisting oit aeasing1 adapted to lie mounted against tlie heated surface of the body of an engine to be served Witli diiect metallic connections from said heated surface to the wall ot the casing at one side thereof; circuit terminals and a temperature-responsive eircuit-closing member, mounted and enclosed in the casing9 the cavity of tlie case Within which said parts are enclosedbeing iilled ivitli oil.

8. device tor the purpose indicated, con sisting oit a double Walled casing with interspace between `tine Walls, adapted to loe n'iount/ed against the heat/ed surface of tlie body ol' an engine to be served with direct metallic connection tro-m said located surface to tlie inner Wall at one side, circuit terminals and a temperature vresponsive circuit closing member mounted and enclosed Within tlie case, 'the interspace between said enclosed parts and the Wall oit the case loeing iilled with oil.

in testimony vvlieieot7 ll liave hereunto set my .liand atcCliieagof, lllinoia this title day of "ileliruaty, i921. 

